The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Apr. 28, 1992
Filed:
Sep. 24, 1991
G.M. Pfaff Aktiengesellschaft, Kaiserslautern, DE;
Abstract
To recognize missed stitches during the operation of a sewing machine, a function, which represents the tensile force of a thread fed into a stitch-forming device depending on the angle of rotation of the main shaft, is scanned in its entirety during each revolution period of the main shaft for selected characteristics without regard to the location of this characteristic within the revolution period. The characteristics found are measured in order to obtain for each characteristic an analytical value that is compared with the corresponding analytical value from at least the last preceding revolution period to form the difference of the two analytical values. If this difference exceeds a predeterminable value, a decision corresponding to a missed stitch is made.